Behavior of Reinforced SCC Short Columns Subjected to Weathering Effects

Bridges & offshore structures are often subjected to fresh and saltwater wet-dry cycles, freeze-thaw cycles in winter, and heating cycles in summer. These environmental effects often cause steel reinforcement corrosion which can be protected using zinc coating. Zinc coating acts as a protective layer for the steel against corrosion. In this paper, the behavior of steel bars with and without zinc coating is investigated. An experimental study is performed on short reinforced concrete columns. Short 50-cm length concrete columns with square 10 × 10-cm cross-section, reinforced by four steel bars of 10-mm diameter are subjected to various weathering effects: accelerated corrosion, cycles of freshwater wet-dry, saltwater wet-dry, Freeze-Thaw (FT) and heating. Self-compacted concrete (SCC) mixes are prepared with 28 MPa average strength. A total of 20 concrete column samples are casted and divided into five groups: 1) salt water-wet-dry-uncoated rebars, 2) salt water-wet-dry-zinc-coated rebars, 3) fresh water-wet-dry-uncoated rebars, 4) heating to 70 °C, and 5) freeze-thaw samples, where 5 samples acted as a control sample and another 5 samples are subjected to accelerated corrosion. The remaining 10 samples are divided among the five groups where each group has 2 samples that are subjected to deterioration cycles. Results indicated that samples subjected to saltwater wet-dry cycles had the least strength among the five groups as expected. However, the diameter and mass losses in accelerated corrosion samples are doubled the values of that of the saltwater dry-wet cycles with the same mean strength.